Maria Sharapova will crown one of tennis's most unlikely comebacks if she regains the title at the $5,000,000 WTA Championships which start on Tuesday.
Sharapova has gradually worked her way back to world number two after an operation in 2008 on a rotator cuff, the kind of shoulder injury from which most players never fully recover.
Arguably the former Wimbledon, US Open, and Australian Open champion still isn't quite the player she was, but has nevertheless achieved her highest ranking in three years and qualified for the tour's climax for the first time since 2007.
There is even an outside chance of Sharapova regaining the world number one ranking, but she would have to win the WTA Championships title whilst Caroline Wozniacki did poorly.
"I just feel a sense of evolvement," said Sharapova.
"You know, this year I feel like I've grown as a player and I've gotten better. It gives me a lot of confidence moving forward."
When Sharapova restarted her career in May 2009 after 10 months out she was only able to serve with a very limited action and was ranked down at 126.
She still does not have the range of overhead function she once had but makes up for some of the loss with better placement.
"I feel like my movement has definitely improved this year," she added. "I think that's because I played a lot of matches. That helps you."
Sharapova has also improved the angles, and changes of pace in her ground strokes with her new coach this year, Thomas Hogstedt, a Swede who has been a very rhythmic ground-stroker himself.
Despite all her setbacks Sharapova's profile has remained high enough for her to remain the highest paid female in sport, and last year she signed an eight-year contract with Nike, worth $70 million, the most lucrative deal ever for a sportswoman.
She was also awarded the WTA Tour's fan favourite singles player, the WTA humanitarian of the year, the WTA most fashionable player (on court), WTA most fashionable player (off court), and even the WTA Tour player with the most dramatic expression!
And this year Sharapova has been named in Forbes magazine as one of the world's 100 most powerful celebrities.
Her comeback is another example of the extraordinary determination, courage, and adaptability which the Russian first showed when leaving home at the age of seven to build a career in what was then to her a very alien country, the United States.
She has also had to recover from a left ankle injury sustained serving against Petra Kvitova in Tokyo, causing her to retire, and then to pull out of the China Open.
Since then Sharapova has said on her official website that the "good news is that the MRI showed no big damage in the ankle", and last week she was quoted on Facebook as saying: "my physio Juan has done an amazing job the last two weeks."
Her earlier than expected arrival in Istanbul created an opportunity to recuperate by re-visiting her childhood haunts at Sochi, on the other side of the Black Sea, little more than 500 miles away.
Sharapova and Wozniacki will be joined at the Sinan Erdem Dome by three of the four Grand Slam winners this year -- Li Na, the French Open champion from China, Kvitova, the Wimbledon champion from the Czech republic, and Samantha Stosur, the US Open champion from Australia.
The other qualifiers, who compete in two round robin groups of four, are Vera Zvonareva, the former runner-up from Russia, Victoria Azarenka, the world number three from Belarus, and Agnieszka Radwanska of Poland who snatched the last place from Marion Bartoli of France only four days before the tournament.
The favourite is Wozniacki, who has made it clear that her greatest ambition is to finish the year as world number one for the second successive time.
However the Dane may also be keen to atone for last year's final, when she held a 3-1 final set lead before losing an enthralling showdown with Kim Clijsters.